1st Edition

Risk and Reliability in Geotechnical Engineering

Edited By Kok-Kwang Phoon, Jianye Ching Copyright 2015
    624 Pages 260 B/W Illustrations
    by CRC Press

    624 Pages 260 B/W Illustrations
    by CRC Press

    Establishes Geotechnical Reliability as Fundamentally Distinct from Structural Reliability

    Reliability-based design is relatively well established in structural design. Its use is less mature in geotechnical design, but there is a steady progression towards reliability-based design as seen in the inclusion of a new Annex D on "Reliability of Geotechnical Structures" in the third edition of ISO 2394. Reliability-based design can be viewed as a simplified form of risk-based design where different consequences of failure are implicitly covered by the adoption of different target reliability indices. Explicit risk management methodologies are required for large geotechnical systems where soil and loading conditions are too varied to be conveniently slotted into a few reliability classes (typically three) and an associated simple discrete tier of target reliability indices.

    Provides Realistic Practical Guidance

    Risk and Reliability in Geotechnical Engineering makes these reliability and risk methodologies more accessible to practitioners and researchers by presenting soil statistics which are necessary inputs, by explaining how calculations can be carried out using simple tools, and by presenting illustrative or actual examples showcasing the benefits and limitations of these methodologies.

    With contributions from a broad international group of authors, this text:

    • Presents probabilistic models suited for soil parameters
    • Provides easy-to-use Excel-based methods for reliability analysis
    • Connects reliability analysis to design codes (including LRFD and Eurocode 7)
    • Maximizes value of information using Bayesian updating
    • Contains efficient reliability analysis methods

    Accessible To a Wide Audience

    Risk and Reliability in Geotechnical Engineering presents all the "need-to-know" information for a non-specialist to calculate and interpret the reliability index and risk of geotechnical structures in a realistic and robust way. It suits engineers, researchers, and students who are interested in the practical outcomes of reliability and risk analyses without going into the intricacies of the underlying mathematical theories.

    Part I


    Constructing multivariate distributions for soil parameters; Jianye Ching and Kok-Kwang Phoon


    Normal random variable

    Bivariate normal vector

    Multivariate normal vector

    Non-normal random variable

    Multivariate non-normal random vector

    Real example

    Future challenges

    List of symbols


    Modeling and simulation of bivariate distribution of shear strength parameters using copulas; Dian-Qing Li and Xiao-Song Tang


    Copula theory

    Modeling bivariate distribution of shear strength parameters

    Simulating bivariate distribution of shear strength parameters

    Impact of copula selection on retaining wall reliability

    Summary and conclusions


    Appendix 2.1: MATLAB® codes

    List of symbols


    Part II


    Evaluating reliability in geotechnical engineering; J. Michael Duncan and Matthew D. Sleep

    Purpose of reliability analysis

    Probability of failure and risk

    Language of statistics and probability

    Probability of failure and factor of safety

    Methods of estimating standard deviations

    Computing probability of failure

    Monte Carlo analysis using @Risk™

    Hasofer Lind method

    Taylor Series method with assumed normal distribution of the factor of safety

    Taylor Series method with a lognormal distribution of the factor of safety

    PEM with a normal distribution for the factor of safety

    PEM with a lognormal distribution for the factor of safety

    Comments on the methods



    Maximum likelihood principle and its application in soil liquefaction assessment; Charng Hsein Juang, Sara Khoshnevisan, and Jie Zhang


    Principle of maximum likelihood

    Liquefaction probability based on generalized linear regression

    Converting a deterministic liquefaction model into a probabilistic model

    Estimation of liquefaction-induced settlement

    Summary and Conclusions


    Appendix 4.1: Model of Robertson and Wride (1998) and Robertson (2009)

    Appendix 4.2: Notation


    Bayesian analysis for learning and updating geotechnical parameters and models with measurements; Daniel Straub and Iason Papaioannou


    Bayesian analysis

    Geotechnical reliability based on measurements: Step-by-step procedure for Bayesian analysis

    Advanced algorithms for efficient and effective Bayesian updating of geotechnical models

    Application: Foundation of transmission towers under tensile loading

    Application: Finite-element-based updating of soil parameters and reliability

    Concluding remarks



    Polynomial chaos expansions and stochastic finite-element methods; Bruno Sudret


    Uncertainty propagation framework

    Polynomial chaos expansions

    Postprocessing for engineering applications

    Sensitivity analysis

    Application examples



    Appendix 6.1: List of symbols

    Appendix 6.2: Hermite polynomials


    Practical reliability analysis and design by Monte Carlo Simulation in spreadsheet; Yu Wang and Zijun Cao


    Subset Simulation

    Expanded RBD with Subset Simulation

    Probabilistic failure analysis using Subset Simulation

    Spreadsheet implementation of MCS-based reliability analysis and design

    Illustrative example I: Drilled shaft design

    Illustrative example II: James Bay Dike design scenario

    Summary and concluding remarks


    List of symbols


    Part III


    LRFD calibration of simple limit state functions in geotechnical soil-structure design; Richard J. Bathurst



    Bias value distributions

    Calculation of β, ϒQ, and φ


    Additional considerations



    Reliability-based design: Practical procedures, geotechnical examples, and insights; Bak-Kong Low


    Example of reliability-based shallow foundation design

    SORM analysis on the foundation of FORM results for a rock slope

    Probabilistic analyses of a slope failure in San Francisco Bay mud

    Reliability analysis of a Norwegian slope accounting for spatial autocorrelation

    System FORM reliability analysis of a soil slope with two equally likely failure modes

    Multicriteria RBD of a laterally loaded pile in spatially autocorrelated clay

    FORM design of an anchored sheet pile wall

    Reliability analysis of roof wedges and rockbolt forces in tunnels

    Probabilistic settlement analysis of a Hong Kong trial embankment on soft clay

    Coupling of stand-alone deterministic program and spreadsheetautomated reliability procedures via response surface or similar methods

    Summary and conclusions


    Managing risk and achieving reliable geotechnical designs using Eurocode 7; Trevor L.L. Orr


    Geotechnical complexity and risk

    Reliability requirements in designs to Eurocode 7

    Verification of designs to Eurocode 7

    Reliability levels




    Part IV

    Risk and decision

    Practical risk assessment for embankments, dams, and slopes; Luis Altarejos-García, Francisco Silva-Tulla, Ignacio Escuder-Bueno, and Adrián Morales-Torres


    Estimation of conditional probability as a function of safety factor

    Role of fragility curves to evaluate the uncertainty in probability estimates

    Mathematical roots and numerical estimation of fragility curves

    From fragility curves to annualized probability of failure commonly used in risk analysis

    Summary of main points


    List of main symbols and acronyms


    Evolution of geotechnical risk analysis in North American practice; Gregory B. Baecher and John T. Christian



    Geotechnical reliability (1971–1996)

    Mining engineering (1969–1980)

    Offshore reliability (1974–1990)

    Environmental remediation (1980–1995)

    Dam safety (1986–Ongoing)

    Systems risk assessment (2005–Ongoing)

    Emerging approaches: System simulation, stress testing, and scenario appraisals

    Ten unresolved questions

    Concluding thoughts



    Assessing the value of information to design site investigation and construction quality assurance programs; Robert B. Gilbert and Mahdi Habibi


    Value of information framework

    Insights from Bayes’ theorem

    Implementation of value of information assessment

    Case-history applications




    Verification of geotechnical reliability using load tests and integrity tests; Limin Zhang


    Within-site variability of pile capacity

    Updating pile capacity with proof load tests

    Updating pile capacity with integrity tests

    Reliability of piles verified by proof load tests

    Reliability of piles verified by integrity tests



    List of symbols


    Part V

    Spatial variability

    Application of the subset simulation approach to spatially varying soils; Ashraf Ahmed and Abdul-Hamid Soubra


    Karhunen–Loève expansion methodology for the discretization of a random field

    Brief overview of the subset simulation approach

    Method of computation of the failure probability by the SS approach in the case of a spatially varying soil property

    Example applications


    Appendix 15.1: Modified M–H algorithm

    List of symbols




    Kok-Kwang Phoon is a distinguished professor and head of the Department of Civil and Environmental Engineering, National University of Singapore, and past president of the Geotechnical Society of Singapore. His main research interests include statistical characterization of geotechnical parameters and reliability-based design in geotechnical engineering. He is the recipient of numerous research awards, including the ASCE Norman Medal in 2005 and the NUS Outstanding Researcher Award in 2010. He is the founding editor of Georisk and chair of TC304 (Engineering Practice of Risk Assessment and Management) in the International Society for Soil Mechanics and Geotechnical Engineering.

    Jianye Ching is a professor in the Department of Civil Engineering, National Taiwan University. His main research interests include geotechnical reliability analysis and reliability-based design, basic uncertainties in soil properties, random fields and spatial variability, and geotechnical design codes. He is the secretary of TC304 (risk) in the International Society for Soil Mechanics and Geotechnical Engineering. He is the recipient of the Outstanding Research Award and the Wu-Da-Yu Memorial Award from the National Science Council of Taiwan, Republic of China.

    "Risk and Reliability in Geotechnical Engineering ...was, originally, to be an update of the 2008 book Reliability-based Design in Geotechnical Engineering – Computations and Applications (edited by K. K. Phoon). The update turns out to be a completely new book, and is a ‘must-read’, not only for those interested in risk and reliability in geotechnical engineering, but also for the geotechnical practitioner."
    Suzanne Lacasse in Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

    "This is a welcome continuation of the very successful volume, Reliability-Based Design in Geotechnical Engineering… Practitioners will find very useful information that range from simple to advanced methods, and from site characterization to design and decision. The book will certainly encourage the use of reliability in practice."
    —Georisk, 2015

    "This is an excellent book, written by acknowledged experts in the field for practicing engineers interested in geotechnical reliability analysis. The presentation is very clear and the subject matter delivered at just the right level – not too mathematical, yet still rigorous in approach. Practical matters, such as designing site investigations and selecting parameters for design, are covered well. Highly recommended."
    —Dr. Andrew Bond, Geocentrix Ltd.

    "The main strength of the materials I have reviewed is that they address the needs and questions of users of many different backgrounds, from practicing engineers who are curious about the added value of doing risk and reliability analyses, but are intimidated by the terminology and mathematics, to professional risk analysts who are more concerned about safety philosophy and application of more advanced analysis methods in assessing the value of information."
    Farrokh Nadim, Technical Director, Norwegian Geotechnical Institute